Decoders also have the difficulty that you need to support most of the format’s features before they can support content found in the wild. Also you often need to add hacks to support encoders which technically violate the specification but are commonly used.
In contrast, you can build a very simple encoder using very few of the format features and still have it be usable/useful (albeit with poor quality/compression ratio).
Not exactly what you are asking for, but jcodec is a pretty readable codebase written in Java. (The readability part is often, ahh, lacking in the source for codecs, in my experience.) It might be a good candidate for rewriting in Rust. https://github.com/jcodec/jcodec
Are there many codecs of any sort with Rust implementations? The majority of Rust stuff I see linked are thin wrappers around existing C or C++ libraries.
